1. Field of the Invention
The disclosure generally relates to a bandgap circuit, and more particularly, relates to a low-offset bandgap circuit and an offset-cancelling circuit therein.
2. Description of the Related Art
A bandgap circuit is widely used as a power supply circuit capable of generating a constant reference voltage or a reference current without being affected by the power supply voltage fluctuation or the temperature fluctuation in a semiconductor device.
However, in fact, the output voltage of a bandgap circuit is often negatively affected by the offset of the operational amplifier therein, and it is more unstable than the ideal case. Accordingly, there is a need to design a new bandgap circuit to reduce its output fluctuation caused by the offset of the operational amplifier.